WASHINGTON -LRB- CNN -RRB- -- The Army and Marine Corps are allowing convicted felons to serve in increasing numbers , newly released Department of Defense statistics show .

A U.S Marine keeps a watchful eye in downtown Baghdad .

Recruits were allowed to enlist after having been convicted of crimes including assault , burglary , drug possession and making terrorist threats .

The statistics were released by Rep. Henry Waxman , a California Democrat who chairs the House Committee on Oversight and Government Reform .

He has given the Pentagon a month to hand over up-to-date details on the number of waivers granted , reports on how the recruits have performed and information about how the waivers are related to meeting recruitment goals .

Pentagon statistics show the Army granted 511 felony waivers in 2007 , just over twice the 249 it granted the year before . The Army aims to recruit more than 80,000 new soldiers a year .

The Marines -- which recruits fewer new service members each year than the Army -- also reported a rise in waivers for felonies , with 350 granted in 2007 , compared with 208 in 2006 .

`` There was a rapid rise in 2007 in the number of waivers the Army and Marine Corps granted to recruits convicted of serious felonies , '' Waxman said in a letter Monday to David Chu , the under-secretary of defense for personnel and readiness .

`` I understand that there can be valid reasons for personnel waivers and recognize the importance of providing opportunities to individuals who have served their sentences and rehabilitated themselves .

`` At the same time , concerns have been raised that the significant increase in the recruitment of persons with criminal records is a result of the strain put on the military by the Iraq war and may be undermining military readiness , '' he charged .

The Army defended its use of waivers as a response to a changing American society , arguing that only three in 10 Americans of military age `` meet all our stringent medical , moral , aptitude or administrative requirements . ''

`` Today 's young men and women are more overweight , have a greater incidence of asthma , and are being charged for offenses that in earlier years would n't have been considered a serious offense , and might not have resulted in charges in the first place , '' John P. Boyce Jr. of Army Public Affairs said in a statement to CNN .

He said the Army never issues waivers for some types of offenses , including sexual violence , alcoholism and drug trafficking .

But the Pentagon statistics showed the Army allowed 106 convicted burglars to enlist in 2007 , up from 36 the year before . It also granted waivers to 43 recruits convicted of aggravated assault that year , up from 33 a year before ; and to 130 people convicted of possession of drugs other than marijuana , a rise from 71 in 2006 .

It also allowed two people convicted of making terrorist or bomb threats to enlist in 2007 , up from one the year before .

The Marines did not immediately respond to request for comment .

The Navy reported a slight decline in felony waivers , from 48 in 2006 to 42 in 2007 . The Air Force said it granted no felony waivers in either year . E-mail to a friend

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Recruits convicted of assault , drug possession , making terrorist threats allowed in

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Rep. Henry Waxman : Defense Department has month to explain waivers

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Army granted 511 felony waivers in 2007 ; Marines granted 350 in 2007

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Army defended waivers , saying fewer recruits today meet their standards